DEVICE FOR DETECTING TRACK ERROR HAVING PHASE DIFFERENCE REMOVING FUNCTION AND PHASE DIFFERENCE REMOVING METHOD THEREFOF

摘要

PURPOSE: A device for detecting a track error having a phase difference removing function is provided to remove all types of phase differences, and to control a phase of a digital signal quantized via an equalizer portion and a comparator portion while removing the phase differences, thereby improving accuracy of a detected track error signal and reducing power consumption. CONSTITUTION: An equalizer portion(110) equalizes a level of an inputted signal to a predetermined level, and consists of equalizers(EQ1-EQ4)(111-114) for equalizing A, B, C, and D signals corresponding to the amount of the light received from A, B, C, and D parts(31,32,33,34) of a light receiving element. A comparator portion(130) consists of comparators(comp1-comp4)(131-134) for quantizing the equalized A1, B1, C1, and D1 signals into digital A2, B2, C2, and D2 signals. A phase shift portion(140) consists of phase shifters(PS1-PS4)(141-144) for removing phase differences among the quantized A2, B2, C2, and D2 signals by a control signal.